tree

#include <iostream>
#include <string>
#include <vector>

using std::cout;
using std::endl;
using std::vector;
using std::string;

namespace chen {

template <typename T>
class Tree {
public:
	Tree(const T& val): val_(val) {}
	T val() const
	{return val_;}
	Tree*& left()
	{return left_;}
	Tree*& right()
	{return right_;}

private:
	T val_;
	Tree* left_;
	Tree* right_;
}; //Tree

template <typename T>
Tree<T>* addVal(Tree<T>* root, const T& val)
{
	if (!root) {
		root = new Tree<T>(val);
		return root;
	}
	if (root->val() > val)
		root->left() = addVal(root->left(), val);
	else
		root->right() = addVal(root->right(), val);

	return root;
}

template <typename T>
void printTree(Tree<T>* root)
{
	if (root) {
		printTree(root->left());
		cout << root->val() << endl;
		printTree(root->right());
	}
}

template <typename T>
void freeTree(Tree<T>** root)
{
	if (*root) {
		freeTree(&(*root)->right());
		freeTree(&(*root)->right());
		delete *root;
		*root = nullptr;
	}
}

void TreeTest()
{
	vector<int> nums = {100, 78, 123, 45, 98, 113, 189, 234, 1, 19, 54, 100, 123, 654, 98};

	chen::Tree<int>* root = 0;
	for (auto i : nums) {
		root = addVal(root, i);
	}
	printTree(root);
	freeTree(&root);
	printTree(root);
}

} //namespace chen